Hii

CBSE has revised the datesheet on 23rd december for class 12th.
You can find the new datesheet on the official website of CBSE. Also i am providing the link for the final datesheet.
http://cbse.nic.in/newsite/circulars/2019/CLASS-X--XII-DATE-SHEET-NEW_FINAL-16-01-2019-3-6.pdf
You can use this link to download the final datesheet of class 12th CBSE.

Hope this helps
Thanks!!